Adam Levine: Shakira 'Will Bust Heads' on 'The Voice'

adam levine predicts shakira will be a killer coach

With a few blind auditions under their belts, the newest coaches on 'The Voice' have demonstrated a level of competitive drive that has impressed show veterans Adam Levine and Blake Shelton.

According to the Maroon 5 rocker, Shakira "is ready to bust some heads."  He explained, "You have a pregnant, hormonal Colombian.  She ain't messing around."

Blake believes that the newbies, including Usher, have changed the dynamic.  He said, "I would say the competitiveness is up.  We've replaced Cee Lo with somebody that's just that much more aggressive.  And Christina was always competitive, but now you've got four that are just killers up here."

Mother-to-be Shakira acknowledged, "Once we are in the process of trying to get a contestant recruited for our team, there's a lot of adrenalin, and there's a lot of tension, but the healthy kind."

Levine said of Usher, "As much as I hate to say this about another coach in the beginning, Usher has done what this show has yet to do.  He has launched a superstar, Justin Bieber, and that's our goal.  That's the shows goal.  That's something we want to do as an institution."

Season 4 premieres March 25, 2013 on NBC.

Photos:  Facebook-NBC The Voice